<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>javascript</title>
  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box
    }
    body {
      font-size: 14px;
      padding: 20px;
    }
    ul li {
      line-height: 30px;
    }
  </style>
</head>
<body>
  <ul>
    <li></li>
  </ul>
</body>
<script src="https://cdn.bootcss.com/vue/2.6.8/vue.js"></script>
<script>
  var obj = {
    a: 1,
    b: 2,
    c: 3,
    d: 4,
  }
  var obj1 = {
    a: 1,
    c: 3
  }
  var arr = Object.keys(obj);
  console.log(arr)
  var arr1 = Object.keys(obj1);
  console.log(arr1)
  arr.forEach((item, index) => {
    if (arr1.includes(item)) {
      arr.splice(index, 1)
    }
  })
  console.log(arr)
</script>
</html>